Display device

ABSTRACT

A display device includes (i) a substrate having a first area, a second area, and a bending area located between the first area and the second area, where the substrate is bent along a bending axis in the bending area, the substrate includes a thin portion at an edge portion of the bending area, and the thin portion extends from the second area to the first area and has a thickness less than a thickness of the substrate at a center of the bending area; and (ii) an inorganic insulating layer over the substrate, where the inorganic insulating layer exposes the thin portion in the bending area.

This application is a continuation of U.S. Pat. Application No.16/880,330, filed on May 21, 2020, which claims priority to KoreanPatent Application No. 10-2019-0156186, filed on Nov. 28, 2019, and allthe benefits accruing therefrom under 35 U.S.C. §119, the content ofwhich in its entirety is herein incorporated by reference.

BACKGROUND 1. Field

One or more exemplary embodiments relate to a display device, and moreparticularly, to a display device capable of minimizing defects in amanufacturing process or a using process after the manufacturingprocess.

2. Description of Related Art

In general, a display device includes a display unit located on asubstrate. Visibility at various angles may be improved or the size of anon-display area may be reduced by bending at least a part of thedisplay device.

SUMMARY

However, in a process of manufacturing a conventional display devicethat is bent or a using process after the manufacturing process, defectsmay occur in a bending portion or a portion near the bending portion.

One or more exemplary embodiments include a display device capable ofminimizing defects in a manufacturing process or a using process afterthe manufacturing process. However, the technical problems are merelyexamples, and the scope of the present disclosure is not limited to thetechnical problems.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented exemplary embodiments of thedisclosure.

According to one or more exemplary embodiments, a display deviceincludes a substrate having a first area, a second area, and a bendingarea disposed between the first area and the second area, where thesubstrate is bent along a bending axis in the bending area, thesubstrate includes a thin portion at an edge portion of the bendingarea, and the thin portion extends from the second area to the firstarea and has a thickness less than a thickness of the substrate at acenter of the bending area; and an inorganic insulating layer over thesubstrate, where the inorganic insulating layer exposes the thin portionin the bending area.

In an exemplary embodiment, the thin portion may define a first grooveextending from the second area to the first area, and the inorganicinsulating layer may have a first opening corresponding to the firstgroove.

In an exemplary embodiment, a width of the first groove may be greaterthan a width of the first opening in the bending axis.

In an exemplary embodiment, an inner side surface of the first openingmay protrude from an edge of the first groove in a direction to a centerof the first opening.

In an exemplary embodiment, the substrate may have a second groovebetween an edge of the substrate and the first groove in the bendingarea, the second groove may extend from the second area to the firstarea, and the inorganic insulating layer may have a second openingcorresponding to the second groove in the bending area.

In an exemplary embodiment, a width of the second groove may be greaterthan a width of the second opening in the bending axis.

In an exemplary embodiment, an inner side surface of the second openingmay protrude from an edge of the second groove in a direction to acenter of the second opening.

In an exemplary embodiment, the second groove may extend nonparallel tothe first groove.

In an exemplary embodiment, the first groove may extend to have a linearshape, and the second groove may extend to have a curved shape.

In an exemplary embodiment, the display device may further include ametal layer which covers an inner side surface of the first opening anda bottom surface of the first groove.

In an exemplary embodiment, a portion of the metal layer on the innerside surface of the first opening and a portion of the metal layer onthe bottom surface of the first groove may be connected to each other.

In an exemplary embodiment, the display device may further include anadditional insulating layer located on the inorganic insulating layerand defining an additional opening corresponding to the first opening inthe bending area.

In an exemplary embodiment, a width of the additional opening may begreater than a width of the first opening in the bending axis.

In an exemplary embodiment, an inner surface of the first opening mayprotrude from an edge of the additional opening to a center of the firstopening.

In an exemplary embodiment, the thin portion may extend up to an end ofthe substrate along the bending axis.

In an exemplary embodiment, an edge of the inorganic insulating layerclose to the thin portion may correspond to an edge of the thin portionin a direction to the center of the bending area.

In an exemplary embodiment, a part of an edge of the thin portion in adirection to the center of the bending area may have a linear shapeextending from the second area to the first area, and a part of an edgeof the inorganic insulating layer in a direction to the thin portion mayhave a linear shape extending from the second area to the first area.

In an exemplary embodiment, the end of the substrate in the bending axismay have a curved shape.

In an exemplary embodiment, an end of the inorganic insulating layerclose to the thin portion may protrude to a center of the thin portion,and a bottom surface of an end portion of the inorganic insulating layerclose to the thin portion may be spaced apart from the substrate.

In an exemplary embodiment, the display device may further include ametal layer which covers a side surface of an end of the inorganicinsulating layer close to the thin portion and a top surface of the thinportion.

In an exemplary embodiment, a portion of the metal layer on the sidesurface of the inorganic insulating layer and a portion of the metallayer on the top surface of the thin portion may be connected to eachother.

In an exemplary embodiment, the display device may further include anadditional insulating layer located on the inorganic insulating layerand exposing a top surface of an end portion of the inorganic insulatinglayer close to the thin portion.

In an exemplary embodiment, the metal layer may cover a part of a topsurface of the inorganic insulating layer.

In an exemplary embodiment, the display device may further include atouch sensor layer over the first area of the substrate, where the touchsensor layer may include a first touch conductive layer, and the metallayer may include the same material as a material of the first touchconductive layer.

In an exemplary embodiment, the display device may further include aprotective layer over the first area and the bending area, where theprotective layer may be interposed between the inorganic insulatinglayer and the touch sensor layer and contact the touch sensor layer, andthe metal layer may be on the protective layer to contact the protectivelayer.

In an exemplary embodiment, the metal layer may have a multi-layerstructure.

In an exemplary embodiment, the display device may further include atouch sensor layer over the first area of the substrate, where the touchsensor layer may include a first touch conductive layer and a secondtouch conductive layer, the metal layer may include a first metal layerincluding the same material as a material of the first touch conductivelayer and a second metal layer including the same material as a materialof the second touch conductive layer and located on the first metallayer.

In an exemplary embodiment, the display device may further include aprotective layer over the first area and the bending area, where theprotective layer may be interposed between the inorganic insulatinglayer and the touch sensor layer and contact the touch sensor layer, andthe first metal layer is on the protective layer to contact theprotective layer.

In an exemplary embodiment, a thickness of a portion of the inorganicinsulating layer corresponding to the bending area may be less than athickness of a portion of the inorganic insulating layer correspondingto a center of the first area.

According to one or more exemplary embodiments, a display deviceincludes a substrate having a first area, a second area, and a bendingarea disposed between the first area and the second area, where thesubstrate is bent along a bending axis in the bending area, thesubstrate has a first groove at an edge portion of the bending area, andthe first groove extends from the second area to the first area; and aninorganic insulating layer over the substrate, where the inorganicinsulating layer exposes the first groove in the bending area.

In an exemplary embodiment, the inorganic insulating layer may have afirst opening corresponding to the first groove.

In an exemplary embodiment, a width of the first groove may be greaterthan a width of the first opening in the bending axis.

In an exemplary embodiment, an inner side surface of the first openingmay protrude from an edge of the first groove in a direction to a centerof the first opening.

In an exemplary embodiment, the substrate may have a second groovebetween an edge of the substrate and the first groove in the bendingarea, the second groove may extend from the second area to the firstarea, and the inorganic insulating layer may have a second openingcorresponding to the second groove in the bending area.

In an exemplary embodiment, a width of the second groove may be greaterthan a width of the second opening in the bending axis.

In an exemplary embodiment, an inner side surface of the second openingmay protrude from an edge of the second groove in a direction to acenter of the second opening.

In an exemplary embodiment, the second groove may extend nonparallel tothe first groove.

In an exemplary embodiment, the first groove may extend to have a linearshape, and the second groove may extend to have a curved shape.

In an exemplary embodiment, the display device may further include ametal layer which covers an inner side surface of the first opening anda bottom surface of the first groove.

In an exemplary embodiment, a portion of the metal layer on the innerside surface of the first opening and a portion of the metal layer onthe bottom surface of the first groove may be connected to each other.

In an exemplary embodiment, the display device may further include anadditional insulating layer over the inorganic insulating layer, wherethe additional insulating layer may have an additional openingcorresponding to the first opening in the bending area.

In an exemplary embodiment, a width of the additional opening may begreater than a width of the first opening in the bending axis.

In an exemplary embodiment, an inner side surface of the first openingmay protrude from an edge of the additional opening in a direction to acenter of the first opening.

In an exemplary embodiment, the metal layer may cover a part of a topsurface of the inorganic insulating layer.

In an exemplary embodiment, the display device may further include atouch sensor layer over the first area of the substrate and including afirst touch conductive layer, where the metal layer may include the samematerial as a material of the first touch conductive layer.

In an exemplary embodiment, the display device may further include aprotective layer over the first area and the bending area, where theprotective layer may be interposed between the inorganic insulatinglayer and the touch sensor layer and contact the touch sensor layer, andthe metal layer may be on the protective layer to contact the protectivelayer.

In an exemplary embodiment, the metal layer may have a multi-layerstructure.

In an exemplary embodiment, the display device may further include atouch sensor layer over the first area of the substrate, where the touchsensor layer may include a first touch conductive layer and a secondtouch conductive layer, where the metal layer may include a first metallayer including the same material as a material of the first touchconductive layer and a second metal layer including the same material asa material of the second touch conductive layer, and the second metallayer may be on the first metal layer.

In an exemplary embodiment, the display device may further include aprotective layer over the first area and the bending area, where theprotective layer may be interposed between the inorganic insulatinglayer and the touch sensor layer and contact the touch sensor layer, andthe first metal layer may be on the protective layer to contact theprotective layer.

In an exemplary embodiment, a thickness of a portion of the inorganicinsulating layer corresponding to the bending area may be less than athickness of a portion of the inorganic insulating layer correspondingto a center of the first area.

Other features and advantages of the present disclosure will become moreapparent from the drawings, the claims, and the detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainexemplary embodiments of the disclosure will be more apparent from thefollowing description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a perspective view illustrating a part of a display deviceaccording to an exemplary embodiment of the present disclosure;

FIG. 2 is a cross-sectional view illustrating the part of the displaydevice of FIG. 1 in a non-bent status;

FIG. 3 is a cross-sectional view illustrating the part of the displaydevice of FIG. 1 in a different direction from FIG. 2 ;

FIG. 4 is a cross-sectional view illustrating a part of a display deviceaccording to another exemplary embodiment of the present disclosure;

FIG. 5 is a cross-sectional view illustrating a part of a display deviceaccording to still another exemplary embodiment of the presentdisclosure;

FIG. 6 is a plan view illustrating a part of a display device accordingto still another exemplary embodiment of the present disclosure;

FIG. 7 is a cross-sectional view illustrating a part of a display deviceaccording to yet another exemplary embodiment of the present disclosure;

FIG. 8 is a plan view illustrating a part of a display device accordingto still another exemplary embodiment of the present disclosure;

FIG. 9 is a cross-sectional view illustrating a part of a display deviceaccording to another exemplary embodiment of the present disclosure;

FIG. 10 is a plan view illustrating a part of a display device accordingto still another exemplary embodiment of the present disclosure;

FIG. 11 is a plan view illustrating a part of a display device accordingto another exemplary embodiment of the present disclosure;

FIGS. 12 through 15 are cross-sectional views illustrating processes ofa method of manufacturing a display device according to anotherexemplary embodiment of the present disclosure;

FIG. 16 is a cross-sectional view illustrating a process of a method ofmanufacturing a display device according to another exemplary embodimentof the present disclosure;

FIG. 17 is a cross-sectional view illustrating a part of a displaydevice according to another exemplary embodiment of the presentdisclosure;

FIG. 18 is a cross-sectional view illustrating a part of a displaydevice according to still another exemplary embodiment of the presentdisclosure;

FIG. 19 is a cross-sectional view illustrating a part of a displaydevice according to yet another exemplary embodiment of the presentdisclosure;

FIG. 20 is a cross-sectional view illustrating a part of a displaydevice according to yet another exemplary embodiment of the presentdisclosure;

FIG. 21 is a cross-sectional view illustrating a part of a displaydevice according to another exemplary embodiment of the presentdisclosure; and

FIG. 22 is a cross-sectional view illustrating a part of a displaydevice according to still another exemplary embodiment of the presentdisclosure.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary embodiments, examplesof which are illustrated in the accompanying drawings, wherein likereference numerals refer to like elements throughout. In this regard,the present exemplary embodiments may have different forms and shouldnot be construed as being limited to the descriptions set forth herein.Accordingly, the exemplary embodiments are merely described below, byreferring to the figures, to explain aspects of the present description.As used herein, the term “and/or” includes any and all combinations ofone or more of the associated listed items. Throughout the disclosure,the expression “at least one of a, b or c” indicates only a, only b,only c, both a and b, both a and c, both b and c, all of a, b, and c, orvariations thereof. The terminology used herein is for the purpose ofdescribing particular embodiments only and is not intended to belimiting. As used herein, the singular forms “a,” “an,” and “the” areintended to include the plural forms, including “at least one,” unlessthe content clearly indicates otherwise. “Or” means “and/or.” It will befurther understood that the terms “comprises” and/or “comprising,” or“includes” and/or “including” when used in this specification, specifythe presence of stated features, regions, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, regions, integers, steps,operations, elements, components, and/or groups thereof.

Hereinafter, exemplary embodiments of the present disclosure will bedescribed with reference to the accompanying drawings, and likereference numerals in the drawings denote like elements and thus theirdescription will not be repeated.

It will be understood that when a component, such as a layer, a film, aregion, or a plate, is referred to as being “on” another component, thecomponent may be directly on the other component or interveningcomponents may be present thereon. Sizes of components in the drawingsmay be exaggerated for convenience of explanation. In other words, sincesizes and thicknesses of components in the drawings are arbitrarilyillustrated for convenience of explanation, the following exemplaryembodiments are not limited thereto. Furthermore, relative terms, suchas “lower” or “bottom” and “upper” or “top,” may be used herein todescribe one element’s relationship to another element as illustrated inthe Figures. It will be understood that relative terms are intended toencompass different orientations of the device in addition to theorientation depicted in the Figures. For example, if the device in oneof the figures is turned over, elements described as being on the“lower” side of other elements would then be oriented on “upper” sidesof the other elements. The exemplary term “lower,” can therefore,encompasses both an orientation of “lower” and “upper,” depending on theparticular orientation of the figure. Similarly, if the device in one ofthe figures is turned over, elements described as “below” or “beneath”other elements would then be oriented “above” the other elements. Theexemplary terms “below” or “beneath” can, therefore, encompass both anorientation of above and below.

In the following exemplary embodiments, the x-axis, the y-axis and thez-axis are not limited to three axes of the rectangular coordinatesystem, and may be interpreted in a broader sense. For example, thex-axis, the y-axis, and the z-axis may be perpendicular to one another,or may represent different directions that are not perpendicular to oneanother. It will be understood that, although the terms “first,”“second,” “third” etc. may be used herein to describe various elements,components, regions, layers and/or sections, these elements, components,regions, layers and/or sections should not be limited by these terms.These terms are only used to distinguish one element, component, region,layer or section from another element, component, region, layer orsection. Thus, “a first element,” “component,” “region,” “layer” or“section” discussed below could be termed a second element, component,region, layer or section without departing from the teachings herein.

FIG. 1 is a perspective view illustrating a part of a display deviceaccording to an exemplary embodiment of the present disclosure. FIG. 2is a cross-sectional view illustrating the part of the display device ofFIG. 1 in a non-bent status. FIG. 3 is a cross-sectional viewillustrating the part of the display device of FIG. 1 in a differentdirection from FIG. 2 .

As shown in FIG. 1 , A display device (especially, a substrate 100referring to FIGS. 2 and 3 ) according to an exemplary embodiment has abending area BA extending in a first direction (e.g., a +y direction)and is bent in the bending area BA. For convenience of illustration andconvenience of explanation, the substrate 100 in FIG. 2 is illustratedas a non-bent status. In a process of manufacturing the display device,the display device illustrated in FIG. 2 is bent in the bending area BAas shown in FIG. 1 . FIG. 2 is a cross-sectional view illustrating afirst area 1A, the bending area BA, and a second area 2A. Forconvenience of illustration and convenience of explanation, thesubstrate 100 in FIG. 3 is illustrated as a non-bent status. FIG. 3 is across-sectional view taken in a direction parallel to a bending axis BAXin the bending area BA.

The substrate 100 has a substantially flat shape before being bent in amanufacturing process of the display device, and when the substrate 100has a flat shape, the bending area BA is disposed between the first area1A and the second area 2A in a second direction (e.g., a +x direction)intersecting with the first direction. The substrate 100 is bent alongthe bending axis BAX that extends in the first direction (e.g., the +ydirection) as shown in FIG. 1 . Although the first area 1A has asubstantially rectangular shape in an x-y plane (i.e., a plane definedby the x direction and y direction) in FIG. 1 , the present disclosureis not limited thereto. Various modifications may be made. In anotherexemplary embodiment, for example, the first area 1A may have asubstantially circular shape. This applies to the following exemplaryembodiments and modifications thereof.

The substrate 100 may include various flexible or bendable materials. Inan exemplary embodiment, for example, the substrate 100 may include apolymer resin such as polyethersulfone, polyacrylate, polyetherimide,polyethylene naphthalate, polyethylene terephthalate, polyphenylenesulfide, polyarylate, polyimide, polycarbonate, or cellulose acetatepropionate. Various modifications may be made. For example, thesubstrate 100 may have a multi-layer structure including two layers 101and 105 that include a polymer resin and a barrier layer 103 thatincludes an inorganic material and is between the layers 101 and 105, asshown in FIGS. 2 and 3 . In this case, the barrier layer 103 may includesilicon oxide, silicon nitride, and/or silicon oxynitride.

Although widths of the first area 1A, the bending area BA, and thesecond area 2A of the substrate 100 along the y-axis are illustrated asnot the same in FIG. 1 , the present disclosure is not limited thereto.In another exemplary embodiment, for example, widths of the first area1A, the bending area BA, and the second area 2A of the substrate 100along the y-axis may be the same. In FIG. 1 , a width in a y-axisdirection is constant at the first area 1A except for a portion of thefirst area 1A adjacent to the bending area BA, decreases gradually atthe portion of the first area 1A adjacent to the bending area BA and ata portion of the bending area BA adjacent to the first area 1A along thesecond direction (e.g., the +x direction) in the non-bent status(Referring to FIG. 6 ), and is constant at a portion of the bending areaBA adjacent to the second area 2A and at the second area 2A.

The first area 1A includes a display area DA. The first area 1A may alsoinclude a part of a non-display area outside the display area DA asshown in FIG. 2 . The second area 2A and the bending area BA alsoinclude a non-display area. The non-display area is an area except forthe display area DA in the display device.

Not only a display element 300 but also a thin-film transistor (“TFT”)210 to which the display element 300 is electrically connected may belocated in the display area DA of the substrate 100 as shown in FIG. 2 .In FIG. 2 , an organic light-emitting element is located as the displayelement 300 in the display area DA. When the organic light-emittingelement is electrically connected to the TFT 210, it may mean that apixel electrode 310 is electrically connected to the TFT 210.

The TFT 210 may include a semiconductor layer 211 including amorphoussilicon polycrystalline silicon or an organic semiconductor material, agate electrode 213, a source electrode 215 a, and a drain electrode 215b. In order to ensure insulation between the semiconductor layer 211 andthe gate electrode 213, a gate insulating film 120 may be disposedbetween the semiconductor layer 211 and the gate electrode 213. The gateinsulating film 120 may include an inorganic material such as siliconoxide, silicon nitride, and/or silicon oxynitride. An interlayerinsulating film 130 may be located on the gate electrode 213. Theinterlayer insulating film 130 may include an inorganic material such assilicon oxide, silicon nitride, and/or silicon oxynitride. The sourceelectrode 215 a and the drain electrode 215 b may be located on theinterlayer insulating film 130. An insulating film including aninorganic material may be provided by using chemical vapor deposition(“CVD”) or atomic layer deposition (“ALD”). This applies to thefollowing exemplary embodiments and modifications thereof.

A barrier layer 111 and a buffer layer 113 which include an inorganicmaterial such as silicon oxide, silicon nitride, and/or siliconoxynitride may be disposed between the TFT 210 and the substrate 100.The barrier layer 111 and the buffer layer 113 may increase a degree offlatness of a top surface of the substrate 100, or may prevent orminimize the penetration of impurities from the substrate 100 or thelike into the semiconductor layer 211 of the TFT 210. The barrier layer111 and the buffer layer 113 may be collectively referred to as aninorganic insulating layer 110.

A planarization layer 140 may be located on the TFT 210. For example,when the organic light-emitting element is located on the TFT 210 asshown in FIG. 2 , the planarization layer 140 may substantiallyplanarize a top surface of a protective film covering the TFT 210. Theplanarization layer 140 may include or be formed of an organic materialsuch as acryl, benzocyclobutene (“BCB”), or hexamethyldisiloxane(“HMDSO”). Although the planarization layer 140 is illustrated as tohave a single-layer structure in FIG. 2 , various modifications may bemade. In another exemplary embodiment, the planarization layer 140 mayhave a multi-layer structure. As shown in FIG. 2 , the planarizationlayer 140 may have an opening outside the display area DA such that aportion of the planarization layer 140 in the display area DA and aportion of the planarization layer 140 in the second area 2A and thebending area BA are physically separated from each other. This is toprevent external impurities from reaching the display area DA throughthe planarization layer 140.

In the display area DA of the substrate 100, the display element 300 maybe located on the planarization layer 140. The display element 300 maybe an organic light-emitting element including the pixel electrode 310,a counter electrode 330, and an intermediate layer 320 that includes anemission layer and is between the pixel electrode 310 and the counterelectrode 330. The pixel electrode 310 is electrically connected to theTFT 210 by contacting any one of the source electrode 215 a and thedrain electrode 215 b through an opening portion formed in theplanarization layer 140 as shown in FIG. 2 .

A pixel-defining film 150 may be located on the planarization layer 140.The pixel-defining film 150 defines a pixel by an opening correspondingto each sub-pixel, that is, an opening through which at least a centralportion of the pixel electrode 310 is exposed. Also, as shown in FIG. 2, the pixel-defining film 150 prevents an arc or the like from occurringat an edge of the pixel electrode 310 by increasing a distance betweenthe edge of the pixel electrode 310 and the counter electrode 330located on the pixel electrode 310. The pixel-defining film 150 mayinclude or be formed of an organic material such as polyimide or HMDSO.

Although the pixel-defining film 150 is located only in the first area1A in FIG. 2 , the present disclosure is not limited thereto. In anotherexemplary embodiment, for example, when the pixel-defining film 150 isformed, an insulating layer (not shown) using the same material as thepixel-defining film 150 may be formed on the planarization layer 140 inthe bending area BA at the same time. This may apply to the followingexemplary embodiments and modifications thereof.

The pixel electrode 310 of the organic light-emitting element may have amulti-layer structure including crystalline indium tin oxide (“ITO”).For example, the pixel electrode 310 may include a reflective layer thatincludes a metal such as aluminum (Al) or copper (Cu), and a transparentconductive layer that includes crystalline ITO and is located on thereflective layer. The counter electrode 330 may also include atransparent conductive layer.

The intermediate layer 320 of the organic light-emitting element mayinclude a low-molecular weight material or a high-molecular weightmaterial. When the intermediate layer 320 includes a low-molecularweight material, the intermediate layer 320 may have a structure inwhich a hole injection layer (“HIL”), a hole transport layer (“HTL”), anemission layer (“EML”), an electron transport layer (“ETL”), and anelectron injection layer (“EIL”) are stacked, and may include any ofvarious organic materials such as copper phthalocyanine (“CuPc”),N,N'-di(naphthalene-1-yl)-N,N'-diphenyl-benzidine (“NPB”), ortris-8-hydroxyquinoline aluminum (“Alq3”). The layers may be formed byusing vacuum deposition.

When the intermediate layer 320 includes a high-molecular weightmaterial, the intermediate layer 320 may have a structure including anHTL and an EML. In this case, the HTL may includePoly(3,4-ethylenedioxythiophene) (“PEDOT”), and the EML may include ahigh-molecular weight material such as a poly-phenylenevinylene(“PPV”)-based material or a polyfluorene-based material. Theintermediate layer 320 may be formed by using screen printing, inkjetprinting, laser induced thermal imaging (“LITI”), or the like.

However, the intermediate layer 320 according to the invention is notlimited thereto, and may have any of various other structures. Inanother exemplary embodiment, the intermediate layer 320 may include alayer that is integrally formed over a plurality of pixel electrodes310, or may include a layer that is patterned to correspond to each of aplurality of pixel electrodes 310.

The counter electrode 330 may be located in the display area DA, tocover the display area DA as shown in FIG. 2 . That is, the counterelectrode 330 may be integrally formed over a plurality of organiclight-emitting elements to correspond to the plurality of pixelelectrodes 310.

Because the organic light-emitting element may be easily damaged byexternal moisture or oxygen, an encapsulation layer 410 may cover andprotect the organic light-emitting element. The encapsulation layer 410may cover the display area DA and may extend to the outside of thedisplay area DA. The encapsulation layer 410 may include a firstinorganic encapsulation layer 411, an organic encapsulation layer 412,and a second inorganic encapsulation layer 413 as shown in FIG. 2 .

The first inorganic encapsulation layer 411 may cover the counterelectrode 330 and may include silicon oxide, silicon nitride, and/orsilicon oxynitride. In another exemplary embodiment, other layers suchas a capping layer may be disposed between the first inorganicencapsulation layer 411 and the counter electrode 330. Because the firstinorganic encapsulation layer 411 is disposed along a contour of thelower structure, a top surface of the first inorganic encapsulationlayer 411 is not flat as shown in FIG. 2 . The organic encapsulationlayer 412 may cover the first inorganic encapsulation layer 411, to havea substantially flat top surface, different from the first inorganicencapsulation layer 411. In detail, a top surface of a portion of theorganic encapsulation layer 412 corresponding to the display area DA maybe substantially flat. In an exemplary embodiment, the organicencapsulation layer 412 may include at least one material selected fromthe group consisting of polyethylene terephthalate, polyethylenenaphthalate, polycarbonate, polyimide, polyethylene sulfonate,polyoxymethylene, polyarylate, and hexamethyldisiloxane. The secondinorganic encapsulation layer 413 may cover the organic encapsulationlayer 412 and may include silicon oxide, silicon nitride, and/or siliconoxynitride. An edge of the second inorganic encapsulation layer 413outside the display area DA may contact the first inorganicencapsulation layer 411 such that the organic encapsulation layer 412 isnot exposed to the outside.

Because the encapsulation layer 410 includes the first inorganicencapsulation layer 411, the organic encapsulation layer 412, and thesecond inorganic encapsulation layer 413, even if cracks occur in theencapsulation layer 410 through such a multi-layer structure, the cracksmay not be connected between the first inorganic encapsulation layer 411and the organic encapsulation layer 412 or between the organicencapsulation layer 412 and the second inorganic encapsulation layer413. Accordingly, the formation of a path through which externalmoisture or oxygen penetrates into the display area DA may be preventedor minimized.

A polarizer 520 may be located on the encapsulation layer 410 by usingan optically clear adhesive (“OCA”) 510. The polarizer 520 may reducethe reflection of external light. In another exemplary embodiment, thepolarizer 520 may be disposed on the encapsulation layer 410 withoutusing the OCA 510.

For example, the polarizer 520 may include a linear polarizer thatpasses only light that is linearly polarized in one direction and a λ/4wave plate that is located under the linear polarizer and convertslinearly polarized light into circularly polarized light. External lightpasses through the polarizer 520, is reflected by a top surface of thecounter electrode 330, and then enters the polarizer 520 again. In thiscase, the external light first passes through the linear polarizer andthen passes through the λ/4 wave plate twice. When the light enters thelinear polarizer again, the light becomes linearly polarized in adirection such that the light may not pass through the linear polarizer.As a result, the reflection of external light may be reduced, therebyimproving the visibility of the display device.

The OCA 510 and the polarizer 520 may cover the opening formed in theplanarization layer 140 as shown in FIG. 2 . The display deviceaccording to an exemplary embodiment does not always include thepolarizer 520. In another exemplary embodiment, the polarizer 520 may beomitted and other elements may be used instead of the polarizer 520. Forexample, the polarizer 520 may be omitted, and a black matrix and acolor filter may be used to reduce the reflection of external light.

The gate insulating film 120 and the interlayer insulating film 130which includes an inorganic material may be collectively referred to asan inorganic insulating film 125. The inorganic insulating film 125 hasan opening portion corresponding to the bending area BA as shown in FIG.2 . That is, the gate insulating film 120 and the interlayer insulatingfilm 130 may have opening portions 120 a and 130 a corresponding to thebending area BA, respectively. When an opening portion corresponds tothe bending area BA, it may mean that the opening portion overlaps thebending area BA. In this case, an area of the opening portion may begreater than that of the bending area BA. To this end, FIG. 2 shows thata width OW of the opening portion is greater than a width BAw of thebending area BA. The area of the opening portion may be defined as anarea of the smallest between areas of the opening portion 120 a formedin the gate insulating film 120 and the opening portion 130 a formed inthe interlayer insulating film 130.

As shown in FIG. 2 , a part of an upper portion of the inorganicinsulating layer 110 located under the inorganic insulating film 125,that is, a part of an upper portion of the buffer layer 113, may also beremoved when the opening portion is formed in the inorganic insulatingfilm 125. As shown in FIG. 2 , a thickness (i.e., length in the zdirection) of a portion of the buffer layer 113 corresponding to theopening portion of the inorganic insulating film 125 is small. That is,a thickness of the inorganic insulating layer 110 at the bending area BAmay be less than a thickness of the inorganic insulating layer 110 atthe center of the first area 1A. In this case, an area of a portion 110a of the inorganic insulating layer 110 having the small thickness maybe defined as an area of the opening portion of the inorganic insulatingfilm 125. FIG. 2 shows that the portion 110 a of the inorganicinsulating layer 110 having the small thickness defines the openingportion of the inorganic insulating film 125.

For reference, in a manufacturing process, the opening portion 120 a ofthe gate insulating film 120 and the opening portion 130 a of theinterlayer insulating film 130 may be simultaneously formed. Becausecontact holes passing through the gate insulating film 120 and theinterlayer insulating film 130 are formed such that the source electrode215 a and the drain electrode 215 b contact the semiconductor layer 211when the TFT 210 is formed, when the contact holes are formed, theopening portion 120 a of the gate insulating film 120 and the openingportion 130 a of the interlayer insulating film 130 may besimultaneously formed. Accordingly, an inner side surface of the openingportion 120 a of the gate insulating film 120 and an inner side surfaceof the opening portion 130 a of the interlayer insulating film 130 mayform a continuous surface as shown in FIG. 2 . When the opening portionsare formed, a part of the upper portion of the inorganic insulatinglayer 110 may also be removed.

The display device according to an exemplary embodiment includes anorganic layer 160 that fills at least a part of the opening portion ofthe inorganic insulating film 125. In FIG. 2 , the organic layer 160entirely fills the opening portion (i.e., the opening portion 130 a, theopening portion 120 a, and the portion 110 a). The display deviceaccording to an exemplary embodiment includes a first conductive layer215 c, and the first conductive layer 215 c extends from the first area1A through the bending area BA to the second area 2A and is located onthe organic layer 160. At a position where the organic layer 160 is notpresent, the first conductive layer 215 c may be located on theinorganic insulating film 125 such as the interlayer insulating film130. The first conductive layer 215 c may be simultaneously formed byusing the same material as the source electrode 215 a or the drainelectrode 215 b.

Although the display device is not bent in FIG. 2 for convenience, thesubstrate 100 or the like in the display device according to the presentexemplary embodiment is actually bendable in the bending area BA asshown in FIG. 1 . To this end, in a manufacturing process, the displaydevice is manufactured in a state where the substrate 100 issubstantially flat as shown in FIG. 2 , and then the display device hassuch a shape as shown in FIG. 1 by bending the substrate 100 or the likein the bending area BA. In this case, although tensile stress may beapplied to the first conductive layer 215 c during a process of bendingthe substrate 100 or the like in the bending area BA, the display deviceaccording to the present exemplary embodiment may prevent or minimizedefects from occurring in the first conductive layer 215 c during thebending process.

If the inorganic insulating film such as the gate insulating film 120and/or the interlayer insulating film 130 does not have the openingportion in the bending area BA and has a continuous shape extending fromthe first area 1A to the second area 2A, and the first conductive layer215 c is located on the inorganic insulating film 125, high tensilestress is applied to the first conductive layer 215 c in a process ofbending the substrate 100 or the like. In particular, because a hardnessof the inorganic insulating film 125 is greater than that of the organiclayer, cracks are likely to occur in the inorganic insulating film 125in the bending area BA, and once cracks occur in the inorganicinsulating film 125, cracks also occur in the first conductive layer 215c on the inorganic insulating film 125 and thus the probability ofdefects such as disconnection of the first conductive layer 215 c isvery high.

In contrast, in the display device according to an exemplary embodimentof the present invention, the inorganic insulating film 125 has theopening portion in the bending area BA, and a portion of the firstconductive layer 215 c in the bending area BA is located on the organiclayer 160 that fills at least a part of the opening portion of theinorganic insulating film 125. Because the inorganic insulating film 125has the opening portion in the bending area BA, cracks are unlikely tooccur in the inorganic insulating film 125, and because the organiclayer 160 includes an organic material, cracks are unlikely to occur inthe organic layer 160. Accordingly, cracks are effectively prevented orminimized from occurring in a portion of the first conductive layer 215c in the bending area BA located on the organic layer 160. Because ahardness of the organic layer 160 is less than that of the inorganiclayer, the organic layer 160 may absorb tensile stress generated whenthe substrate 100 or the like is bent, thereby effectively minimizingconcentration of the tensile stress on the first conductive layer 215 c.

Although the inorganic insulating layer 110 formed of an inorganicmaterial exists in the bending area BA, because a thickness of theinorganic insulating layer 110 is relatively small, the probability thatdefects occur due to bending is very low. In particular, because athickness of the inorganic insulating layer 110 in the bending area BAis less than a total thickness of the inorganic insulating layer 110 andthe inorganic insulating film 125 in the first area 1A as describedabove, the substrate 100 or the like may be smoothly bent and defectsmay be effectively prevented. In addition, because the organic layer 160exists in the bending area BA and the first conductive layer 215 c islocated on the organic layer 160, the first conductive layer 215 c maybe effectively prevented from being damaged by bending.

The display device according to an exemplary embodiment may includesecond conductive layers 213 a and 213 b in addition to the firstconductive layer 215 c. The second conductive layers 213 a and 213 b maybe located in the first area 1A and the second area 2A, respectively,and be located in a layer different from a layer in which the firstconductive layer 215 c is located. The second conductive layers 213 aand 213 b may be electrically connected to the first conductive layer215 c. In FIG. 2 , the second conductive layers 213 a and 213 b arelocated on the same layer (i.e., on the gate insulating film 120) andinclude the same material as the gate electrode 213 of the TFT 210. Thefirst conductive layer 215 c contacts the second conductive layers 213 aand 213 b through the contact hole of the interlayer insulating film130. In addition, the second conductive layer 213 a is located in thefirst area 1A, and the second conductive layer 213 b is located in thesecond area 2A.

The second conductive layer 213 a located in the first area 1A may beelectrically connected to the TFT 210 or the like in the display areaDA, and thus, the first conductive layer 215 c may be electricallyconnected to the TFT 210 or the like in the display area DA through thesecond conductive layer 213 a. The second conductive layer 213 b locatedin the second area 2A may also be electrically connected to the TFT 210or the like in the display area DA by the first conductive layer 215 c.The second conductive layers 213 a and 213 b may be located outside thedisplay area DA and may be electrically connected to elements located inthe display area DA, or the second conductive layers 213 a and 213 b maybe located outside the display area DA and may extend to the displayarea DA such that at least a part of the second conductive layers 213 aand 213 b is located inside the display area DA.

Although the display device is not bent in FIG. 2 for convenience, thesubstrate 100 or the like in the display device according to the presentexemplary embodiment is actually bendable in the bending area BA asshown in FIG. 1 . To this end, in a manufacturing process, the displaydevice is manufactured in a state where the substrate 100 issubstantially flat as shown in FIG. 2 , and then the display device hassuch a shape as shown in FIG. 1 by bending the substrate 100 or the likein the bending area BA. In this case, tensile stress may be applied tothe first conductive layer 215 c during a process of bending thesubstrate 100 or the like in the bending area BA.

Accordingly, the first conductive layer 215 c crossing the bending areaBA may include a material having a high elongation, to prevent cracksfrom occurring in the first conductive layer 215 c or defects such asdisconnection from occurring in the first conductive layer 215 c. Thesecond conductive layers 213 a and 213 b including a material having anelongation lower than that of the first conductive layer 215 c andelectrical/physical characteristics different from those of the firstconductive layer 215 c may be disposed in the first area 1A or thesecond area 2A, to improve the efficiency of electrical signaltransmission in the display device or reduce defects in a manufacturingprocess.

For example, the second conductive layers 213 a and 213 b may includemolybdenum, and the first conductive layer 215 c may include aluminum.In an exemplary embodiment, the first conductive layer 215 c or thesecond conductive layers 213 a and 213 b may have a multi-layerstructure. For example, the first conductive layer 215 c may have amulti-layer structure including a titanium layer, an aluminum layer, anda titanium layer, and the second conductive layers 213 a and 213 b mayhave a multi-layer structure including a molybdenum layer and a titaniumlayer. However, the present disclosure according to the invention is notlimited thereto. In another exemplary embodiment, the first conductivelayer 215 c may extend to the display area DA and may be directlyconnected to the source electrode 215 a, the drain electrode 215 b, orthe gate electrode 213 of the TFT 210. Also, in still another exemplaryembodiment, different from in FIG. 2 , various modifications may bemade. For example, a conductive layer that is formed at the same time byusing the same material as the gate electrode 213 may be located on theorganic layer 160 and may extend to the display area DA.

As shown in FIG. 2 , the organic layer 160 may cover an inner sidesurface of the opening portion of the inorganic insulating film 125. Thefirst conductive layer 215 c may be formed at the same time with thesource electrode 215 a and the drain electrode 215 b and include thesame material as the source electrode 215 a and the drain electrode 215b as described above. To this end, the source electrode 215 a, the drainelectrode 215 b, and the first conductive layer 215 c may be provided byforming a conductive layer over an entire surface of the substrate 100(more specifically, over an entire surface of the interlayer insulatingfilm 130) and patterning the conductive layer. In a case that theorganic layer 160 does not cover the inner side surface of the openingportion 120 a of the gate insulating film 120 or the inner side surfaceof the opening portion 130 a of the interlayer insulating film 130, aconductive material may remain on the inner side surface of the openingportion 120 a of the gate insulating film 120 or the inner side surfaceof the opening portion 130 a of the interlayer insulating film 130without being removed from the inner side surface in a process ofpatterning the conductive layer. In this case, the remaining conductivematerial may cause a short between different conductive layers.Accordingly, it is preferable that when the organic layer 160 is formed,the organic layer 160 covers the inner side surface of the openingportion of the inorganic insulating film 125.

To this end, as shown in FIG. 2 , the organic layer 160 may have adifferent thickness according to a position, and a top surface of theorganic layer 160 near the inner side surface of the opening portion 120a of the gate insulating film 120 or the inner side surface of theopening portion 130 a defined the interlayer insulating film 130 may beflat. Accordingly, in the process of patterning the conductive layer toform the source electrode 215 a, the drain electrode 215 b, and thefirst conductive layer 215 c, the conductive material may be effectivelyprevented from remaining without being removed.

A bending protection layer (“BPL”) 600 may be located outside thedisplay area DA. That is, the BPL 600 may be located on the firstconductive layer 215 c to correspond to at least the bending area BA.

When a stack is bent, there is a stress neutral plane somewhere in thestack. The stress neutral plane may refer to a plane which does notreceive a tensile or compressive stress or receive minimum stress in thestack when the stack is bent. In a case that the BPL 600 is notincluded, excessive tensile stress or the like may be applied to thefirst conductive layer 215 c in the bending area BA when the substrate100 or the like is bent. This is because a position of the firstconductive layer 215 c may not correspond to the stress neural plane.

However, in an exemplary embodiment according to the invention, the BPL600 may be provided and a position of the stress neural plane may beadjusted in a stack including the substrate 100, the first conductivelayer 215 c, and the BPL 600 by adjusting a thickness, a modulus, etc.of the BPL 600. Accordingly, the stress neural plane may be located nearor over the first conductive layer 215 c by the BPL 600, to minimizetensile stress applied to the first conductive layer 215 c or to makecompressive stress to be applied to the first conductive layer 215 c.The BPL 600 may include or be formed of acryl or the like. Whencompressive stress is applied to the first conductive layer 215 c, theprobability that the first conductive layer 215 c is damaged is muchlower than that when tensile stress is applied.

Although an end of a top surface of the BPL 600 in a direction to thedisplay area DA in the first area 1A is matched to a top surface of thepolarizer 520 in a +z direction in FIG. 2 , the present disclosure isnot limited thereto. In another exemplary embodiment, for example, theend of the BPL 600 in the direction to the display area DA may cover apart of a top surface of an edge of the polarizer 520. In still anotherexemplary embodiment, the end of the BPL 600 in the direction to thedisplay area DA may not contact the polarizer 520 and/or the OCA 510. Inparticular, in the latter case, in or after a process of forming the BPL600, gas generated in the BPL 600 may be prevented from moving in thedirection (e.g., a -x direction) toward the display area DA, therebypreventing the display element 300 such as an organic light-emittingelement from being degraded by the gas.

When the end of the top surface of the BPL 600 in the direction to thedisplay area DA is matched to the top surface of the polarizer 520 inthe +z direction, the end of the BPL 600 in the direction to the displayarea DA covers a part of the top surface of the edge of the polarizer520, or the end of the BPL 600 in the direction to the display area DA(e.g., the -x direction) contacts the OCA 510, a thickness (i.e., lengthin z-axis direction) of the end portion of the BPL 600 in the directionto the display area DA may be greater than a thickness of anotherportion of the BPL 600 as shown in FIG. 2 . Because a paste material maybe coated and cured to form the BPL 600, a volume of the BPL 600 may bereduced in a curing process. Therefore, if the end portion of the BPL600 in the direction to the display area contacts the polarizer 520and/or the OCA 510, since a position of the end portion of the BPL 600is fixed, a volume reduction occurs in a remaining portion of the BPL600. As a result, the thickness of the end portion of the BPL 600 in thedirection to the display area DA may be greater than the thickness ofanother portion of the BPL 600.

Because the inorganic insulating film 125 has the opening portioncorresponding to at least the bending area BA as described above,defects due to bending may be minimized. However, because the inorganicinsulating layer 110 exists in the bending area BA even though theinorganic insulating layer 110 in the bending area BA has a smallthickness, defects may occur in the inorganic insulating layer 110 ofthe bending area BA. In particular, because the inorganic insulatinglayer 110 may be exposed at edges of the substrate 100 facing away eachother in the y-axis direction in the bending area BA or the inorganicinsulating layer 110 is located near the edges of the substrate 100facing away each other in the y-axis direction as shown in FIG. 3 ,stress may be concentrated on the end portion of the inorganicinsulating layer 110 and defects of the display device may occur, whenthe substrate 100 or the like is bent in a manufacturing process. Theleft part of FIG. 3 illustrates a center portion of the substrate 100 inthe bending area BA, and the right part of FIG. 3 illustrates the endportion of the substrate 100 in the +y direction in the bending area BA.The end portion of the inorganic insulating layer 110 is vulnerable toexternal impact even after manufacturing and may be easily damaged,thereby causing defects of the display device. Accordingly, in order tominimize the occurrence of defects, the display device according to anexemplary embodiment has a structure as shown in FIG. 3 .

In detail, the substrate 100 includes a thin portion located at an edgeportion of the bending area BA in the y-axis direction and having athickness less than a thickness at the center of the bending area BA.Referring to FIG. 3 , the thin portion of the substrate 100 defines afirst groove 100 a. The first groove 100 a defined in the thin portionmay extend from the second area 2A to the first area 1A (e.g., in the -xdirection of the coordinate axis of FIG. 2 ). When the substrate 100 hasa multi-layer structure including two layers 101 and 105 including apolymer resin and the barrier layer 103 including an inorganic materialand located between the layers 101 and 105 as shown in FIG. 3 , thelayer 105 disposed in a direction to the inorganic insulating layer 110may define the first groove 100 a. Although FIG. 3 illustrates a centralportion of the display device in the bending area BA in the left partand an edge portion of the display device in the +y direction in thebending area BA in the right part, an edge portion in the bending areaBA in a -y direction may have a structure that is the same as or similarto that of the edge in the +y direction in the bending area BA. Here,the edge portion in the bending area BA in the +y direction may bereferred to the rightmost portion of the bending area BA when thebending area is divided by five or four portions each portion of whichhas an equal length in the y axis direction.

The inorganic insulating layer 110 located on the substrate 100 exposesthe thin portion of the substrate 100 in the bending area BA. In FIG. 3, the inorganic insulating layer 110 defines a first opening 110 bcorresponding to the first groove 100 a to expose the first groove 100 aof the substrate 100. When the first opening 110 b exposes the firstgroove 100 a, it may not mean that the first opening 110 b entirelyexposes the first groove 100 a but mean that the first opening 110 bexposes at least a part of the first groove 100 a. In FIG. 3 , the firstopening 110 b exposes a central portion of the first groove 100 a.

Because the substrate 100 has the first groove 100 a and the inorganicinsulating layer 110 has the first opening 110 b, defects may bedramatically prevented or minimized. For example, because impact islikely to be applied to an edge in the +y direction or an edge in the -ydirection in the bending area BA and a stress is concentrated in abending process, cracks may occur in an edge of the inorganic insulatinglayer 110 in the +y direction or the -y direction in the bending areaBA. In a case that the cracks grow to the central portion of the bendingarea BA, cracks may occur even in a wiring such as the first conductivelayer 215 c, thereby adversely affecting the display device.

However, in the display device according to an exemplary embodimentaccording to the invention, the substrate 100 has the first groove 100 aand the inorganic insulating layer 110 has the first opening 110 b. Thefirst opening 110 b extends along the edge of the substrate 100 (e.g.,in the +x direction when a bent state is disregarded). Accordingly, evenwhen cracks occur in the edge of the inorganic insulating layer in the+y direction or the -y direction, the cracks may not grow to the centralportion of the bending area BA and may stop near the first opening 110b. Accordingly, even when a stress is applied to the bending area BA ina manufacturing process or impact is applied to the outside of thebending area BA in the manufacturing process or a using process afterthe manufacturing process, defects due to the cracks in central portionof the display device may be effectively prevented or minimized.

As shown in FIG. 3 , a width W1 of the first groove 100 a of thesubstrate 100 in the y-axis direction may be greater than a width W2 ofthe first opening 110 b of the inorganic insulating layer 110 in they-axis direction. Accordingly, an inner side surface of the firstopening 110 b of the inorganic insulating layer 110 may protrude from anedge of the first groove 100 a of the substrate 100 to the center of thefirst opening 110 b. Accordingly, a portion of a bottom surface of theinorganic insulating layer 110 over the first opening 110 b may bespaced apart from the substrate 100.

The organic layer 160 and the planarization layer 140 are located on theinorganic insulating layer 110 even in the bending area BA as shown inFIG. 3 . The organic layer 160 and/or the planarization layer 140 may bereferred to as an additional insulating layer 170, and the additionalinsulating layer 170 on the inorganic insulating layer 110 has anadditional opening corresponding to the first opening 110 b in thebending area BA as shown in FIG. 3 . Because a width of the additionalopening is greater than a width W2 of the first opening 110 b, an innerside surface of the first opening 110 b protrudes from an edge of theadditional opening to the center of the first opening 110 b. Thisapplies to the following exemplary embodiments and modificationsthereof.

FIG. 4 is a cross-sectional view illustrating a part of a display deviceaccording to another exemplary embodiment of the present disclosure. Thedisplay device according to the present exemplary embodiment isdifferent from the display device of FIG. 3 in that the substrate 100has a second groove 100 b in addition to the first groove 100 a, and theinorganic insulating layer 110 has a second opening 110 c in addition tothe first opening 110 b. The second groove 100 b is disposed between anedge of the substrate 100 and the first groove 100 a in the bending areaBA, and extends from the second area 2A to the first area 1A (e.g., inthe x-axis direction). The second opening 110 c has a shapecorresponding to the second groove 100 b in the bending area BA. Becausethe display device includes the second groove 100 b and the secondopening 110 c in addition to the first groove 100 a and the firstopening 110 b, even when cracks occur in an edge of the inorganicinsulating layer 110 in the +y direction or the -y direction in thebending area BA, defects may be effectively prevented from occurring inthe display device.

In this case, a width of the second groove 100 b of the substrate 100 inthe y-axis direction may be greater than a width of the second opening110 c of the inorganic insulating layer 110 in the y-axis direction.Accordingly, an inner side surface of the second opening 110 c of theinorganic insulating layer 110 may protrude from an edge of the secondgroove 100 b of the substrate 100 to the center of the second opening110 c.

As shown in FIGS. 3 and 4 , the first conductive layer 215 c that may bereferred to as a wiring and located on the organic layer 160 and extendfrom the first area 1A through the bending area BA to the second area 2Ais located on a central portion (in the y-axis direction) of thesubstrate 100 in the bending area BA. Although the first conductivelayer 215 c may not be between the first groove 100 a and the secondgroove 100 b of the substrate 100 in FIG. 4 , the present disclosureaccording to the invention is not limited thereto. For example, as shownin FIG. 5 that is a cross-sectional view illustrating a part of adisplay device according to still another exemplary embodiment of thepresent disclosure, the first conductive layer 215 c may be located onthe organic layer 160 provided between the first groove 100 a and thesecond groove 100 b. Because the number of various wirings increases ina high-resolution display device, such a structure as shown in FIG. 5may be used. This applies to the following exemplary embodiments andmodifications thereof.

FIG. 6 is a plan view illustrating a part of a display device accordingto still another exemplary embodiment of the present disclosure. Thedisplay device is not bent in FIG. 6 . A cross-sectional view of FIGS. 4or 5 may be a cross-sectional view in the bending area BA of FIG. 6 .

As shown in FIG. 6 , the second groove 100 b may not be parallel to thefirst groove 100 a. That is, the first groove 100 a may have a linearshape extending from the second area 2A to the first area 1A (e.g.,x-axis direction), and the second groove 100 b may have a curved shapeextending from the second area 2A to the first area 1A.

For example, as shown in FIG. 6 , the display device may have a shapehaving an edge that is concave in and near the bending area BA. That is,a width of the substrate 100 in the y-axis direction decreases graduallyat a portion of the first area 1A adjacent to the bending area BA and ata portion of the bending area BA adjacent to the first area 1A along thesecond direction (e.g., the +x direction), and is constant at a portionof the bending area BA adjacent to the second area 2A and at the secondarea 2A.

In this case, the second groove 100 b located closer to an edge of thesubstrate 100 than the first groove 100 a may have a curved shapecorresponding to a shape of the edge of the substrate 100. The firstgroove 100 a that is not directly affected by the shape of the edge ofthe substrate 100 may have a substantially linear shape extending fromthe second area 2A to the first area 1A different from the second groove100 b, to effectively prevent cracks occurring in an edge of theinorganic insulating layer 110 (in the +y direction or the -y direction)from growing to a central portion of the bending area BA, or the firstarea 1A or the second area 2A.

In general, cracks occurring in the edge of the inorganic insulatinglayer 110 (in the +y direction or the -y direction) grow in a direction(e.g., the -y direction or the +y direction) substantially perpendicularto a straight line (parallel to the x-axis) that connects the first area1A and the second area 2A. Accordingly, the first groove 100 a which issubstantially perpendicular to the direction in which the cracks growmay effectively prevent or minimize defects.

FIG. 7 is a cross-sectional view illustrating a part of a display deviceaccording to yet another exemplary embodiment of the present disclosure.The display device according to the present exemplary embodiment isdifferent from the display device of FIG. 4 in that the substrate 100does not include the second groove 100 b. Instead, the substrate 100includes a thin portion 100 c outside the first groove 100 a, and thethin portion 100 c extends up to an end of the substrate 100 along thebending axis BAX (e.g., the +y direction).

In this case, an edge 110 d of the inorganic insulating layer 110 closeto or in a direction to the thin portion 100 c (e.g., the +y direction)corresponds to an edge of the thin portion 100 c close to or in adirection to the center of the bending area BA (e.g., the -y directionin FIG. 7 ). As shown in FIG. 7 , the edge 110 d of the inorganicinsulating layer 110 in the direction to the thin portion 100 c (e.g.,the +y direction) may not be exactly matched to the edge of the thinportion 100 c in a direction to the center of the bending area BA in thedirection (e.g., the -y direction). That is, as shown in FIG. 7 , theedge 110 d of the inorganic insulating layer 110 close to or in adirection to the thin portion 100 c (e.g., the +y direction) mayprotrude from the edge of the thin portion 100 c close to or in adirection to the center of the bending area BA (e.g., the -y directionin FIG. 7 ) toward the center of the thin portion 100 c (e.g., the +ydirection), and a bottom surface of the edge 110 d of the inorganicinsulating layer 110 close to or in the direction to the thin portion100 c may be spaced apart from the substrate 100 in the z-axisdirection.

The thin portion 100 c may have a curved shape extending along an edgeof the substrate 100 like the second groove 100 b of FIG. 6 , as shownin FIG. 8 that is a plan view illustrating a part of a display deviceaccording to still another exemplary embodiment of the presentdisclosure. In this case, the first groove 100 a may have a linear shapeextending from the second area 2A to the first area 1A.

Although the substrate 100 includes the first groove 100 a and also thethin portion 100 c in FIG. 7 , the present disclosure is not limitedthereto. In another exemplary embodiment, for example, as shown in FIG.9 that is a cross-sectional view illustrating a part of a display deviceaccording to another exemplary embodiment of the present disclosure, thesubstrate 100 may not have the first groove 100 a and may include onlythe thin portion 100 c. That is, the substrate 100 may include the thinportion 100 c at an edge in the bending area BA (e.g., in the +ydirection and the -y direction), and the thin portion 100 c may extendalong the bending axis BAX (e.g., the +y direction) up to an end of thesubstrate 100.

In this case, the edge 110 d of the inorganic insulating layer 110 closeto or in a direction to the thin portion 100 c (e.g., the +y direction)corresponds to an edge of the thin portion 100 c in a direction to thecenter of the bending area BA (e.g., the -y direction in FIG. 9 ). Asshown in FIG. 9 , the edge 110 d of the inorganic insulating layer 110close to or in the direction to the thin portion 100 c (e.g., the +ydirection) may not be exactly matched to the edge of the thin portion100 c in the direction to the center of the bending area BA (e.g., the-y direction). That is, as shown in FIG. 9 , the edge 110 d of theinorganic insulating layer 110 close to or in the direction to the thinportion 100 c(e.g., the +y direction) may protrude from the edge of thethin portion 100 c close to or in a direction to the center of thebending area BA (e.g., the -y direction in FIG. 9 ) toward the center ofthe thin portion 100 c (the +y direction), and a bottom surface of theedge 110 d of the inorganic insulating layer 110 close to or in thedirection to the thin portion 100 c may be spaced apart from thesubstrate 100 in the z-axis direction.

As shown in FIG. 9 , the organic layer 160 and the planarization layer140 are located on the inorganic insulating layer 110 even in thebending area BA. The organic layer 160 and/or the planarization layer140 may be referred to as an additional insulating layer 170, and theadditional insulating layer 170 on the inorganic insulating layer 110exposes a top surface of the edge 110 d of the inorganic insulatinglayer 110 close to or in a direction to the thin portion 100 c in thebending area BA as shown in FIG. 9 . This may apply to the followingexemplary embodiments and modifications thereof as well as the exemplaryembodiment of FIG. 7 .

The thin portion 100 c may have a curved shape extending along an edgeof the substrate 100 like the second groove 100 b of FIG. 6 , as shownin FIG. 10 that is a plan view illustrating a part of a display deviceaccording to still another exemplary embodiment of the presentdisclosure. In another exemplary embodiment, the edge of the thinportion 100 c in a direction to the center of the bending area BA mayhave a linear shape extending from the second area 2A to the first area1A, as shown in FIG. 11 that is a plan view illustrating a part of adisplay device according to another exemplary embodiment of the presentdisclosure. In this case, the edge 110 d of the inorganic insulatinglayer 110 close to or in a direction to the thin portion 100 c may alsohave a linear shape extending from the second area 2A to the first area1A. The end of the substrate 100 along the bending axis BAX (e.g., the+y direction or the -y direction) has a curved shape.

A method of forming the first groove 100 a and the first opening 110 bof FIG. 3 , that is, a method of manufacturing a display device, will bedescribed with reference to FIGS. 12 through 15 . First, various layersare formed on the substrate 100, and the pixel electrode 310 through thepixel-defining film 150 are formed. Although not shown in FIG. 12 thatis a cross-sectional view in the bending area BA, the pixel-definingfilm 150 may be located on the planarization layer 140 in the bendingarea BA.

Next, a mask layer ML defining an open area is formed as shown in FIG.13 by forming a layer on the planarization layer 140 and/or thepixel-defining film 150 and patterning the layer. The mask layer ML mayinclude or be formed of indium zinc oxide (“IZO”) or amorphous ITO. Forexample, the open area may be formed by forming a layer corresponding toan entire surface of the substrate 100 by using IZO or amorphous ITO andremoving a part of the layer at a position where the first groove 100 ais to be formed by using a photoresist.

When dry etching is performed in this situation, the first opening 110 bis of the inorganic insulating layer 110 by removing the inorganicinsulating layer 110 at a portion corresponding to the open area of themask layer ML as shown in FIG. 14 , and when dry etching is furtherperformed, the substrate 100 is undercut and the first groove 100 a isof the substrate 100. The mask layer ML protects other elements that arepreviously formed in the display area DA, etc. during the dry etching.

Next, the display device of FIG. 3 may be manufactured by removing themask ML of FIG. 14 by performing entire wet etching and then forming theintermediate layer 320 on the pixel electrode 310.

Because the mask layer ML is formed after the pixel electrode 310 andthe pixel-defining film 150 are formed as described above, a portion ofthe pixel electrode 310 not covered by the pixel-defining film 150contacts the mask layer ML. Accordingly, when the mask layer ML isremoved by using wet etching, it is preferable not to damage the pixelelectrode 310 or the like.

Because the mask layer ML is formed of IZO or amorphous ITO as describedabove, an etch rate of the IZO or the amorphous ITO is very differentfrom an etch rate of crystalline ITO. The etch rate of the IZO or theamorphous ITO is also very different from an etch rate of silicon oxide,silicon nitride, or the like. Accordingly, even when the mask layer MLformed of IZO or amorphous ITO is removed by using wet etching, otherelements including the pixel electrode 310 may not be damaged during theremoval process.

The first groove 100 a of the substrate 100 and the first opening 110 bof the inorganic insulating layer 110 directly contact the BPL 600 inthe above exemplary embodiments. However, the present disclosure is notlimited thereto.

In another exemplary embodiment, for example, a display device may bemanufactured by forming the first groove 100 a of the substrate 100 andthe first opening 110 b of the inorganic insulating layer 110 as shownin FIG. 15 , forming a metal layer MTL covering an inner side surface ofthe first opening 110 b and a bottom surface of the first groove 100 aas shown in FIG. 16 , and forming the BPL 600 as shown in FIG. 17 . Inthis case, a portion of the metal layer MTL on the inner side surface ofthe first opening 110 b and a portion of the metal layer MTL on thebottom surface of the first groove 100 a may be connected to each other.Furthermore, the metal layer MTL may cover a part of a top surface ofthe inorganic insulating layer 110.

The metal layer MTL may protect the inner side surface of the firstopening 110 b of the inorganic insulating layer 110, and may block thegrowth of cracks. When the display device includes the second opening110 c and the second groove 100 b as shown in FIGS. 4 or 5 , an innerside surface of the second opening 110 c and a bottom surface of thesecond groove 100 b may also be covered by a metal layer. In this case,the metal layer MTL covering the inner side surface of the first opening110 b and the bottom surface of the first groove 100 a may not beconnected to and may be spaced apart from the metal layer covering theinner side surface of the second opening 110 c and the bottom surface ofthe second groove 100 b.

When a metal layer is formed in the display area DA or the first area1A, the metal layer MTL may be simultaneously formed by using the samematerial as the metal layer in the display area DA. For example, whenthe counter electrode 330 (see FIG. 2 ) is formed, the metal layer MTLmay be simultaneously formed by using the same material. Alternatively,a touch sensor layer (not shown) including a touch conductive layer maybe formed on the encapsulation layer 410 after the encapsulation layer410 is formed and before the polarizer 520 is attached or formed. Whenthe touch conductive layer is formed, the metal layer MTL may besimultaneously formed by using the same material as the touch conductivelayer. The touch conductive layer refers to any of various electrodes ora bridge wiring for performing a touchscreen function. This applies tothe following exemplary embodiments and modifications thereof.

As shown in FIG. 18 that is a cross-sectional view illustrating a partof a display device according to still another exemplary embodiment ofthe present disclosure, in a case that the substrate 100 does not havethe first groove 100 a but includes the thin portion 100 c extending upto an end of the substrate 100 along the bending axis BAX (e.g., the +ydirection), the metal layer MTL may cover a side surface of an end ofthe inorganic insulating layer 110 close to or in a direction to thethin portion 100 c and may cover a top surface of the thin portion 100c. In this case, a portion of the metal layer MTL on the side surface ofthe inorganic insulating layer 110 and a portion of the metal layer MTLon the top surface of the thin portion 100 c may be connected to eachother.

The metal layer MTL of FIGS. 17 and 18 may be formed at the same time byusing the same material as the touch conductive layer as describedabove. As shown in FIG. 19 which is a cross-sectional view illustratinga part of a display device according to yet another exemplary embodimentof the present disclosure, the display device may further include atouch sensor layer SENL located in the first area 1A of the substrate100. A protective layer CL may be interposed between the touch sensorlayer SENL and the polarizer 510. The present invention is not limitedhereto such that the polarizer 520 and OCA 510 may be located over thetouch sensor layer SENL and the protective layer CL may contact theencapsulation layer 410. The touch sensor layer SENL may include sensingelectrodes SE and driving electrode DE. The sensing electrodes may beextended in y-axis and connected one another, and each of the sensingelectrodes may have an opening corresponding to a corresponding pixelelectrode 310 in order not to hinder light generated in the EML frompropagating outside. The driving electrodes DE may be arranged in x-axisand separated one another. The driving electrodes DE can be electricallyconnected one another through bridge electrodes BE located between theprotective layer CL and a touch insulating layer TINS1. The bridgeelectrodes BE may be located to correspond to an area between adjacentpixel electrodes 310. The driving electrode DE may also have an openingcorresponding to a corresponding pixel electrode 310 in order not tohinder light generated in the EML from propagating outside. The touchinsulating layer TINS1 insulates the bridge electrodes BE from thesensing electrodes SE. The driving electrodes DE can be connected to thebridge electrodes BE through contact holes in the touch insulating layerTINS1. Another touch insulating layer TINS2 may cover the sensingelectrodes SE and the driving electrodes DE. The touch conductive layeraforementioned may be the sensing electrodes SE or the drivingelectrodes DE, or may be the bridge electrode BE. The metal layer MTLmay include the same material as that of the first touch conductivelayer.

As explained above, before the touch sensor layer SENL is formed, theprotective layer CL may be formed on the encapsulation layer 410 byusing silicon oxide, silicon nitride, or silicon oxynitride, and thetouch sensor layer SENL may be formed on the protective layer CL. Inthis case, the protective layer CL is between the inorganic insulatinglayer 110 and the touch sensor layer SENL, and contacts a bottom surfaceof the touch sensor layer SENL. The protective layer CL may also beformed in the bending area as well as the first area 1A, and in thiscase, the metal layer MTL is located on the protective layer CL andcontacts the protective layer CL.

FIG. 20 illustrates that a protective layer CL covers a side surface ofan end of the inorganic insulating layer 110 close to or in a directionto the thin portion 100 c and covers a top surface of the thin portion100 c, and the metal layer MTL is located on the protective layer CL.Even in the structure of FIG. 17 , the protective layer may be furtherlocated under the metal layer MTL. In this case, when the touchconductive layer of the touch sensor layer SENL is formed, a conductivelayer may be formed on the protective layer CL and may be patterned toform the bridge electrodes BE. When the conductive layer is patterned toform the bridge electrodes BE, the protective layer CL and theconductive layer may be simultaneously patterned in the same manner.Accordingly, the protective layer in the first area 1A may have the samepattern as the bridge electrodes BE (unlike the structure shown in FIG.19 ), and likewise, the protective layer CL may have the same pattern asthe metal layer MTL as shown in FIG. 20 .

The metal layer MTL may have a multi-layer structure. As explainedabove, the touch sensor layer SENL may have the sensing electrodes SE,the driving electrodes DE, and the bridge electrode BE located in thefirst area 1A of the substrate 100. In this case, the metal layer MTLmay include a first metal layer including the same material as that ofthe bridge electrode BE and a second metal layer including the samematerial as that of the sensing electrode SE and the driving electrodeDE and located on the first metal layer. While the sensing insulatinglayer TINS1 may be between the bridge electrode BE and the sensingelectrode SE in the first area 1A, an insulating layer may be not formedin the bending area BA and thus the first metal layer and the secondmetal layer contact each other.

Even in this case, the protective layer CL may be between the inorganicinsulating layer 110 and the touch sensor layer SENL, may contact thetouch sensor layer SENL, and may be located in the first area 1A and thebending area BA. The first metal layer may be located on the protectivelayer CL to contact the protective layer CL (see FIG. 20 ) in thebending area BA. The protective layer CL in the bending area BA may bespaced apart from the protective layer CL in the first area 1A. This isbecause when the bridge electrode BE is formed by patterning theconductive layer as described above, the protective layer CL under thebridge electrode BE is also simultaneously patterned in the samepattern.

FIG. 21 is a cross-sectional view illustrating a part of a displaydevice according to another exemplary embodiment of the presentdisclosure. The display device according to the present exemplaryembodiment further includes a protective conductive layer 215 d locatedon the inorganic insulating layer 110 in the bending area BA as shown inFIG. 21 . Because a thickness of the inorganic insulating layer 110 issmall, the substrate 100 may be bent without a big problem, but cracksmay occur in the inorganic insulating layer 110 in the bending area BAdue to a stress applied in a bending process or impact applied in ausing process after the display device is manufactured. Although suchcracks may not be a problem because the organic layer 160 is located onthe inorganic insulating layer 110 in the bending area BA, in order toprevent the cracks from affecting the first conductive layer 215 c onthe organic layer 160, the protective conductive layer 215 d may befurther located on the inorganic insulating layer 110 in the bendingarea BA.

In this case, the protective conductive layer 215 d may besimultaneously formed by using the same material as the source electrode215 a and the drain electrode 215 b when the source electrode 215 a andthe drain electrode 215 b of the TFT 210 in the first area 1A areformed. In this case, a passivation layer 132 may cover the TFT 210, andthe first conductive layer 215 c may be simultaneously formed by usingthe same material as a wiring (not shown) located on the passivationlayer 132 when the wiring located on the passivation layer 132 isformed.

When the display device includes the protective conductive layer 215 d,as shown in FIG. 22 that is a cross-sectional view illustrating a partof a display device according to still another exemplary embodiment ofthe present disclosure, the protective conductive layer 215 d may alsobe located on a portion of the inorganic insulating layer 110 locatedbetween the first groove 100 a of the substrate 100 and an edge of thesubstrate 100 in the +y direction.

According to an exemplary embodiment of the present disclosure, adisplay device capable of minimizing defects in a manufacturing processor a using process after the manufacturing process may be provided.However, the scope of the present disclosure is not limited by theeffects.

It should be understood that exemplary embodiments described hereinshould be considered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each exemplaryembodiment should typically be considered as available for other similarfeatures or aspects in other exemplary embodiments. While one or moreexemplary embodiments have been described with reference to the figures,it will be understood by those of ordinary skill in the art that variouschanges in form and details may be made therein without departing fromthe spirit and scope as defined by the following claims.

What is claimed is:
 1. A display device comprising: a substrate having afirst area, a second area, and a bending area disposed between the firstarea and the second area, wherein the substrate is bent along a bendingaxis in the bending area, the substrate comprises a thin portion at anedge portion of the substrate in the bending area, the thin portionextends from the second area to the first area along the edge portion ofthe substrate, and a thickness of the substrate at the thin portion inthe bending area is less than a thickness of the substrate at a centerof the first area; and an inorganic insulating layer over the substrate,wherein the inorganic insulating layer exposes the thin portion in thebending area, wherein the thin portion defines a first groove extendingfrom the second area to the first area, and the inorganic insulatinglayer has a first opening corresponding to the first groove.
 2. Thedisplay device of claim 1, wherein a width of the first groove isgreater than a width of the first opening in a direction of the bendingaxis.
 3. The display device of claim 1, wherein an inner side surface ofthe first opening protrudes from an edge of the first groove in adirection to a center of the first opening.
 4. The display device ofclaim 1, wherein the substrate has a second groove between an edge ofthe substrate and the first groove in the bending area, the secondgroove extends from the second area to the first area, and the inorganicinsulating layer has a second opening corresponding to the second groovein the bending area.
 5. The display device of claim 4, wherein a widthof the second groove is greater than a width of the second opening in adirection of the bending axis.
 6. The display device of claim 4, whereinan inner side surface of the second opening protrudes from an edge ofthe second groove in a direction to a center of the second opening. 7.The display device of claim 4, wherein the second groove extendsnonparallel to the first groove.
 8. The display device of claim 4,wherein the first groove extends to have a linear shape, and the secondgroove extends to have a curved shape.
 9. The display device of claim 1,further comprising a metal layer which covers an inner side surface ofthe first opening.
 10. The display device of claim 1, further comprisingan additional insulating layer over the inorganic insulating layer,wherein the additional insulating layer has an additional openingcorresponding to the first opening in the bending area.
 11. A displaydevice comprising: a substrate having a first area, a second area, and abending area disposed between the first area and the second area,wherein the substrate is bent along a bending axis in the bending area,the substrate has a first groove at an edge portion of the substrate inthe bending area, the first groove is a recessed part of the substrateat the edge portion of the substrate, a thickness of the substrate atthe first groove is less than a thickness of the substrate at a centerof the first area, and the first groove extends from the second area tothe first area along the edge portion of the substrate; and an inorganicinsulating layer over the substrate, wherein part of the inorganicinsulating layer on the bending area exposes the first groove in thebending area; wherein inorganic insulating layer has a first openingcorresponding to the first groove.
 12. The display device of claim 11,wherein a width of the first groove is greater than a width of the firstopening in a direction of the bending axis.
 13. The display device ofclaim 11, wherein an inner side surface of the first opening protrudesfrom an edge of the first groove in a direction to a center of the firstopening.
 14. The display device of claim 11, wherein the substrate has asecond groove between an edge of the substrate and the first groove inthe bending area, the second groove extends from the second area to thefirst area, and the inorganic insulating layer has a second openingcorresponding to the second groove in the bending area.
 15. The displaydevice of claim 14, wherein a width of the second groove is greater thana width of the second opening in a direction of the bending axis. 16.The display device of claim 14, wherein an inner side surface of thesecond opening protrudes from an edge of the second groove in adirection to a center of the second opening.
 17. The display device ofclaim 14, wherein the second groove extends nonparallel to the firstgroove.
 18. The display device of claim 14, wherein the first grooveextends to have a linear shape, and the second groove extends to have acurved shape.
 19. The display device of claim 11, further comprising ametal layer which covers an inner side surface of the first opening. 20.The display device of claim 11, further comprising an additionalinsulating layer over the inorganic insulating layer, wherein theadditional insulating layer has an additional opening corresponding tothe first opening in the bending area.